I didn't read your proposal, so I'm not totally sure about it, but I can respond in terms of MMP. The question is, how you would actually elect the list MPs. Is it by province or by region? I'm not sure.
We do see situations where, if you have a region, you get a lot of candidates, say, from the urban part of the province or from the city. Parties usually have a vested interest in preventing that from happening, because it creates an opportunity for other parties to elect list candidates from the other parts of the province. So parties sometimes solve that issue on their own.
On the actual unit of election for list MPs, what we see in practice with list MPs is that they're less interested in geography than constituency MPs are. They take on different representational concerns, different foci representations. A lot of women list MPs see it as their job to represent the interests of women. People from certain groups take these different, non-geographically defined interests as the groups of people they would represent. This happens no matter what you use, province or region, and it's what we would probably expect to see in Canada as well if we had these kinds of list MPs being elected alongside constituency MPs.